Young U.S. gymnasts prepare at Pan Ams for Rio rumble

TORONTO (Reuters) - The most exciting names in U.S. gymnastics, Gabby Douglas, Aly Raisman and Simone Biles, will all be competing during the Pan American Games -- just not in Toronto.

But the absence of the American big guns has not prevented the United States from dominating the Pan Am competition where a new crop of champions are putting the old guard on notice that they will have a battle on their hands for coveted Rio Olympic berths.

Two-time world all-around champion Biles, Douglas, the darling of the 2012 London Olympics, and her gold medal-winning Fierce Five team mates Raisman and Kyla Ross, are all competing at the U.S. Classic in Chicago on July 25.

Their absence from the Pan Am games has given the U.S. squad of hungry up and comers an opportunity to grab the spotlight.

For the first time in 20 years the U.S. swept both the men's and women's team gold medals, while Sam Mikulak claimed the men's all-around title to end a 28-year American drought in that event.

The only blip came on Monday when women's all-around favorite Madison Desch was beaten for the gold by Canada's Ellie Black, but the young Americans vowed a return to the top of the podium in the apparatus finals.

"That (Rio Olympics) is what I have been working for and hopefully this is the start of great things," said Desch. "I know I can improve. It is just the start.